The present invention generally relates to shelters for wild birds. More particularly, the present invention concerns a birdhouse assembly that attracts purple martins and encourages the successful breeding of this species.
Bird watching is a highly prevalent past time in both urban and rural areas. The world is full of birds of numerous varieties in an astounding array of colors and designs. Many people enjoy viewing birds of various types, and an industry has evolved around products directed to improving the ability of persons to closely observe birds in their natural environment. On one hand, many people venture into the outdoors, where binoculars and spotting scopes may be utilized to better view various birds in their natural habitats. Such an approach requires a certain degree of skill, however, in finding and spotting various species of birds. Another approach utilizes various means of attracting birds to one's residence or a desired viewing location, such as adjacent a home's porch or window, where birds may be viewed at one's leisure. For example, persons have used bird feeders, birdbaths, and the like to attract birds of various types to their homes.
Various species of birds can be attracted by providing suitable nesting sites that accommodate their needs and protect them from predators. Certain birds, such as purple martins and bluebirds are welcome additions to one's backyard because of the mutually beneficial relationship that exists between these birds and their “landlords”. Purple martins, in particular, are highly desirable additions to one's backyard because they play such an important role in the control of mosquito population. In fact, studies have indicated that a single purple martin can eat up to 2,000 mosquitoes and other insects a day. In addition, purple martins are interesting and beautiful creatures that enjoy living together in colonies that enable one to observe their interactions with one another. They also possess superior flight capabilities that enable them to perform daily aerial acrobatics, which provides much enjoyment to many a birdwatcher.
Purple martins were first attracted to hollowed out gourds, which were placed about Native American villages. However, as Native American villages began to disappear, so did the gourds, and by the middle of the twentieth century, purple martins were nearly extinct. The near extinction of these remarkable birds prompted great efforts to understand their habits and provide housing suitable for nesting. Today, purple martins are totally dependent upon man-made housing and studies continue to reveal new ways to improve their nesting sites and encourage breeding.
There are general specifications that a suitable purple martin house should have to provide attract purple martins. For example, purple martin houses should be set between fifteen (15) and twenty (20) feet off the ground. Also, the nesting compartments should be large enough to accommodate both the adult-sized parents and approximately four (4) to six (6) nearly grown fledgings. Accordingly, many specifications recommend that the nesting compartment be at least 6″×6″, but deeper compartments, such as those that measure between 8-12″ from front to back, have been observed to offer better protection against predators. Textured floors in the nesting compartments are also beneficial because they help prevent abnormalities that develop if the infant slips while moving about in the compartment. Since purple martins prefer to live together in colonies, a plurality of individual nesting compartments can be grouped together to accommodate as many as a couple dozen pairs of purple martins.
Entryways into the nesting compartments should also be sized to permit entry by an adult sized purple martin and are preferably of a pattern that keeps out predator birds such as starlings. For example, studies have indicated that some predator birds, such as starlings, are unable to gain access to the nesting compartment through a crescent shaped entryway.
Additionally, to increase breeding success, it is important that the nesting compartments be properly managed. Interestingly, access to the individual nesting compartments during the nesting season has shown to encourage successful breeding because it allows for the regular monitoring and care of the nesting compartments. These so-called nest checks allow the landlord to discover whether the nests are being preyed upon by owls at night, or by hawks or other predator birds by day. Early detection of predator activity will enable a landlord to take certain precautions to save the remainder of the nest. Nest checks also permit the landlord to remove unwanted nests such as those made by birds not welcome in a purple martin house.
In order to carry out these nest checks, it is helpful for the purple martin house to be easily lowered in way that does not harm the eggs or infant birds. In fact, many purple martin houses currently in use or on the market are not capable of being lowered and their respective landlords may never realize that the nests are being preyed upon.
As a result, some purple martin houses appearing in the market place are capable of being lowered so as to permit the landlord to conduct nest checks. Assemblies that enable the birdhouses to be lowered, however, preferably return the birdhouse to its original position so that each nesting compartment is in the same relative position and compass direction. This is because after the purple martin house is again elevated back to its original location, the adult purple martins will typically only return to the nesting compartment based upon its compass direction. If the birdhouse is repositioned causing the adult purple martins to trespass on another's nest, the adult purple martin becomes confused, which often results in abandonment of the nests and eventual loss of the eggs or fledglings.
To encourage the successful breeding of purple martins, then, improved housing assemblies are needed that protect purple martin nests from predators and enable their landlords to perform nest checks. While various housing assemblies currently in use today meet some of the minimum specifications, such as compartment sizes and entryway dimensions, nesting compartments are still readily accessible by predators. Additionally, typical nesting compartments are easily exposed to wind-blown rain, which dampens the nest and may result in a loss of the featherless infants that will become chilled in a damp nest. Further, now that studies have indicated the importance of monitoring the nesting compartments of the purple martin houses during the nesting season, it is desirable to provide an improved assembly that safely and efficiently permits the landlord to perform the nest checks.